Thermoformed container

ABSTRACT

A thermoformed container comprises a tray having walls that join a bottom surface and form an opening opposite the bottom surface. The walls are curved where they join the bottom surface. A tray flange surrounds the opening and extends outwardly from the walls. A lid has a recessed panel surrounded by peripheral sides, wherein the lid and the tray are configured to lock together. A lid flange surrounds the peripheral sides and extends outwardly therefrom. Marks on the bottom surface are configured to indicate increments of the bottom surface.

FIELD OF THE INVENTION

The present invention relates generally to the field of plasticpackaging and particularly to thermoformed containers.

BACKGROUND

Packaging of a wide variety of food products has increasingly usedthermoformed containers. The wide variety of food products is typicallyheld in the thermoformed containers until consumed by a consumer or fora period of time corresponding to an adequate shelf life of thecontained food products. The thermoformed containers may be reclosableor re-sealable to protect food products, such as spreads, dips and thelike, with a cover or lid. The thermoformed container may be designed tobe an adaptable combination of a tray and a lid. The lid for suchreclosable thermoformed containers is disconnectedly adapted to fit aflange of the tray to permit access to an interior of the container.Depending upon the type of food products, the tray is typically designedto be formed with one or more compartments.

The thermoformed containers are typically formed by heating a plasticsheet between two heated platens and drawing it down into a mold cavityor over a form utilizing vacuum, or pressure, or both. The thermoformedplastic containers are rigid or semi-rigid plastic film structures withrelatively sturdy walls, of the type that are intended for long-term useby the consumer. The thermoformed containers are useful for hot and coldfoods as they provide a degree of thermal insulation.

Conventionally, a retail bar package for cream cheese is difficult toopen and remove the product. The retail cream cheese package can be awrapper folded over a rectangular shaped cream cheese bar and sealedalong two short sides and a longer side of the wrapper. Retail creamcheese can also often be hot filled as a liquid into a pouch and thensealed, cooled and cartoned. In addition the current retail cream cheesepackages are not equipped with re-sealable sides or edges. Further,consumers generally tend to desire a product packaging that provides avisual marking that may denote an incremental division of the packagedproduct.

In view of the above discussed problems, it would desirable to provide arigid reclosable thermoformed container that facilitates easy removal ofthe packaged product and that includes incremental markings.

BRIEF SUMMARY

In accordance with an embodiment of the present invention, athermoformed container comprises a tray having walls that join a bottomsurface and form an opening opposite the bottom surface. The walls arecurved where they join the bottom surface. A tray flange surrounds theopening and extends outwardly from the walls. A lid has a recessed panelsurrounded by peripheral sides, wherein the lid and the tray areconfigured to lock together. A lid flange surrounds the peripheral sidesand extends outwardly therefrom. Marks on the bottom surface areconfigured to indicate increments of the bottom surface.

In another embodiment of the invention, a thermoformed container forholding a food product comprises a tray having walls that join a bottomsurface and form an opening opposite the bottom surface. The walls arecurved where they join the bottom surface. A tray flange surrounds theopening and extends outwardly from the walls. A lid has a recessed panelsurrounded by peripheral sides, such that the lid and the tray areconfigured to lock together. A lid flange surrounds the peripheral sidesand extends outwardly therefrom. Marks on the bottom surface areconfigured to indicate increments of the bottom surface, such thatimages corresponding to the marks are transposed on the food productafter settling into the tray, to enable easy division of the foodproduct into increments corresponding to the marks when the food productis removed from the thermoformed container.

In yet another embodiment, a combination of a food product in athermoformed container comprises a volume of food extruded out of ametering device and settled into a tray of the thermoformed container.At least one image on a bottom surface of the food product correspondsto at least one mark on a bottom surface of the tray. The at least oneimage enables easy division of the food product into increments when thefood product is removed from the thermoformed container.

Further aspects and advantages of the invention are described below inconjunction with the present embodiments

BRIEF DESCRIPTION OF THE DRAWING

The invention, together with the advantages thereof, may be understoodby reference to the following description in conjunction with theaccompanying figures, which illustrate some embodiments of theinvention:

FIG. 1 is a perspective assembly view of a thermoformed container with atray and a lid in accordance with one embodiment of the invention;

FIG. 2 is shows perspective views of the thermoformed containerillustrated in FIG. 1 with the lid removed from the tray;

FIG. 3 a-3 d are a bottom view and a cross-sectional view along line A-Aof the assembled container, a close up of a cross sectional view of lidprojections engaged with tray grooves along circle C, and a bottom viewof the lid in accordance with an embodiment of the invention; and

FIG. 4 is a bottom perspective view of the assembled thermoformedcontainer illustrated in FIG. 1.

DETAILED DESCRIPTION

While the present invention may be embodied in various forms, there isshown in the drawings and will hereinafter be described some exemplaryand non-limiting embodiments, with the understanding that the presentdisclosure is to be considered an exemplification of the invention andis not intended to limit the invention to the specific embodimentsillustrated.

In this application, the use of the disjunctive is intended to includethe conjunctive. The use of definite or indefinite articles is notintended to indicate cardinality. In particular, a reference to “the”object or “an” object is intended to denote also one of a possibleplurality of such objects.

Referring to FIG. 1, a thermoformed container 10 is generally shown. Thethermoformed container 10 has a tray 12 and a lid 14. Both the tray 12and the lid 14 are generally box-like structures. The tray 12 is formedby a sidewall having four interconnected peripheral walls 16 and 18,namely two opposing long walls 16, and two opposing short walls 18. Inaddition, the tray 12 has diagonally opposed corners 20 and 22. Thediagonally opposed corners 20 and 22 are diagonally pair matched inrelation to tray 12. The lid 14 is formed by a relatively shallowsidewall having four interconnected peripheral sides 24 and 26, namelytwo opposing long sides 24 and two opposing short sides 26. The fourinterconnected peripheral sides 24 and 26 are commonly connected at oneend to a recessed panel 27. The peripheral sides 24 and 26 form adepression surrounded by a peripheral lid flange 28 that extendsoutwardly therefrom.

Referring to FIG. 2, the four peripheral walls 16 and 18 taper at onerespective end to an integral bottom wall 25, and form at anotherrespective end an opening 37. The opening 37 is surrounded by a trayflange 38 that extends outwardly therefrom. The diagonally opposedcorners 20 and 22 are thus pair matched diagonally in relation to thebottom wall 25. As such, one diagonal pair of corners 20 has a largerradius than that of the other diagonal pair of corners 22. Alternately,corners 20, and 22 can have substantially the same radius.

The peripheral lid flange 28 has a bottom surface that substantiallymirrors an upper surface of the tray flange 38 for sealing purposes.Alternately, the lid flange 28 may overlap the tray flange 38 in atleast one corner. For example, to enable an ease of opening of thecontainer 10 in one corner the lid flange 28 may be configured with acorrespondingly greater radius than the tray flange 38.

Still referring to FIG. 2, a thermoformed container 10 is provided as anadaptable reclosable combination of the tray 12 and the lid 14. Toprevent access to an interior of the container 10, an externalperipheral side surface of lid 14 adjacent to the lid flange 28 isconfigured to fit an interior peripheral surface of the tray sidewalladjacent to the top flange 38. The recessed panel 27 facilitates pushingthe lid 14 down into the opening 37 of the tray 12 to lock the lid 14onto the tray 12 to close the thermoformed container 10. Accordingly,the lid 14 will be securely positioned in the tray 12. By locking thelid 14 to the tray 12, inadvertent or otherwise undesirable opening ofthe container 10 prior to an intentional opening can be substantiallyminimized. In one embodiment, the peripheral sides 24 and 26 of the lid14 have a depth of about ⅛″ to about ¼″, and more preferably about ¼″.

In accordance with an embodiment of the invention, the lid 14 sealablycloses the tray 12 in a substantially tight closure while rendering thecontainer 10 readily openable. The substantially tight closure of thecontainer 10 minimizes any release of the closure due to jerky andmotions of the closed container 10. The closure also provides protectionfrom the outside environment while the container 10 is closed. Thecontainer 10 is preferably configured to be opened with a moderateamount of force by a smooth and constant pulling force applied to thelid 14. Alternately, the closure minimizes a susceptibility to leaking.

Referring to FIGS. 3 a-3 d, in one embodiment of the invention, toenhance the closure of the container 10, the tray 12 includes grooves 29and the lid 14 includes projections 39. The grooves 29 open on theinside surface of the tray walls 16 and 18 are formed along asubstantially horizontal direction near the tray flange 38. The grooves29 project outwardly from the outside surface of the tray walls 16 and18. The projections 39 are formed in horizontal series in the peripheralsides 24 and 26 near the lid flange 38, and project outwardly thereform.The grooves 29 engage the corresponding projections 39 to secure the lid14 to the tray 12. When the tray 12 is closed with the lid 14, thedownward sliding movement of the lid 14 into the tray 12 is arrestedwhen lid projections 39 snap into the corresponding grooves 29. Thoseskilled in the art will appreciate several alternative structuresconfigured to secure the lid 14 to the tray 12. For example, lockinglugs, and the like can be configured in the tray 12 and the lid 14.

In one alternate embodiment, the tray 12 and the lid 14 include taperedsides and walls to create a friction fit type of locking or securingclosure of the container 10. In another alternate embodiment, the lidflange 28 and the tray flange 38 include a pressure sensitive adhesivethat enables the container 10 to be opened and reclosed.

In a preferred embodiment, the tray 12 and the lid 14 are formed from arigid plastic film structure. The rigid plastic film structure acts anoxygen barrier to improve the shelf life of the food products enclosedin the thermoformed container 10. The tray 12 is formed out of a moldedsingle sheet of thermoplastic material. In the molding process, thebottom wall 25 is concavely molded near the upwardly extending walls 16,and 18.

Preferably, both the tray 12 and the lid 14 are made from materials thatcontain a release or non-stick agent such as glycerol mono stearate, andthe like. The release agent allows the contained products to be easilyremoved or popped out of container 10 by the consumer. Alternately, theinner surfaces of the tray 12 and a bottom surface of the lid 14 can betreated with a suitable releasing agent in order to prevent sticking.For example, by applying the releasing agent to the inner surfaces ofthe tray 12, a block of cheese can be removed substantially in itsentirety from the tray 12.

When initially filled, the container 10 is hermetically sealed acrossthe tray flange 38 and the lid flange 28. The tray flange 38 and lidflange 28 are provided with sealant layers 41 on respective mirrorsurfaces. That is, the sealant layers 41 are applied to a top surface ofthe tray flange 38 that mirror a bottom surface of the lid flange 28. Inone embodiment, the sealant layer 41 is a peelable seal that allows thelid 14 to be easily removed from the tray 12 by the consumer. Thesealant layers 41 are designed to release the lid flange 28 from thetray flange 38 by a cohesive failure of the seal. To facilitate easyopening of the container 10, the sealant layers 41 are applied to theentire sealing surfaces of the flanges 28 and 38. Accordingly, thesealant layers 41 are not heat sealed along a distal portion of at leastone of the flange corners of both the tray 12 and the lid 14. In thisway, the container 10 is easily opened at the corresponding corners ofthe tray 10.

The sealant layers 41 can also enable the container 10 to be resealedwhen the sealant layers 41 of the tray flange 38 and the lid flange 28come in contact with each other again. The sealant layers 41 cancomprise pressure sensitive adhesive to facilitate opening andre-closing of the tray 12 with the lid 14. In the preferred embodiment,the container 10 and the sealant layers 41 are strong enough that thecontainer 10 will not bulge or burst when a stacking pressure is appliedto the container 10. For example, the container 10 is subjected tostacking pressure when positioned in a similar stack of containers 10.The sealant layers 41 protect food products in the container 10 fromoxygen and moisture. The peelable sealing layers 41 are designed topromote a separation of the closing surfaces of the lid flange 28 andthe tray flange 38 with a moderate amount of force. Concurrently, thelid 14 is readily removable from the tray 12 to provide access to theinterior of the container 10.

Once the seal has been broken, the container 10 may be opened byapplying opposing finger pressures to the lid flange 28 and to the trayflange 38. Alternately, overlapping release tabs (not shown) can beincluded in the lid flange 28 or in the tray flange 38, or both, whichextend outwardly to provide finger graspable regions. In one embodiment,the lid 14 has instructional indicia positioned on the lid flange 28.For example, the lid flange 28 can include instructions to the consumeron how to break the seal and how to separate the lid 14 from the tray14.

From the foregoing, the tray 12 and the lid 14 can be locked together bypushing down on the recess panel 27 of the lid 14, or by engaging theprojections 39 into the grooves 29 or by the sealant layers 41 when thelid flange 28 and the tray flange 38 are brought into contact with oneanother, or by any combination of these alternatives.

A cream cheese product is preferably packaged under conditions such thatthe package has an adequate shelf life, in an unopened and refrigeratedstate, of at least three months, and, more preferably, at least fourmonths or longer. Referring to FIG. 4, for home or other retail uses,the thermoformed container 10 may preferably contain about 4 ounces toabout 16 ounces and more preferably, about 8 ounces of food product,such as for example cream cheese. In one preferred embodiment, raisedmarks 42 are formed into the bottom wall 25 of the tray 12. The raisedmarks 42 are configured to transpose their respective images onto thecontained food product. Corresponding marks 44, such as numbers orletters, or both, are also formed into the tray 12 and are alsoconfigured to transpose their images to the contained food product. Inone embodiment, the marks 44 indicate the size of the increments, forexample 1 oz. In this preferred embodiment, when the contained foodproduct is removed from the tray 12 and deposited upside down onto aworking surface, the tranposed raised marks 42 and 44 enable theconsumer to easily divide the product in uniform increments.Alternately, the marks 42 or 44, or both, may be formed onto at leastone sidewall 16, and 18 of the tray 12.

In a preferred embodiment, the tray 12 and the lid 14 are configured toprovide a relatively stable stack of filled containers 10. For example,it is desirable that a stack of containers remain in vertical alignmentwith no substantial lateral play between the lids and the trays of eachcontainer. To enable the containers 10 to be stacked to a desiredheight, an inner surface of the recess panel 27 is configured toaccommodate the concave surface of the bottom wall 25 of the tray 12. Assuch, the bottom wall 25 is configured to substantially engage the nextadjacent lid 14 in the stack of containers 10 while minimizing a lateralmovement of the stacked containers 10 relatively to one another.Accordingly, configuring the tray 12 and lid 14 in accordance with thepreferred embodiment enable the containers 10 to be stacked in such away so as not to become jammed together when subjected to an axialcompressive load.

In one embodiment, packing of the tray 12 with food products, such ascheese, is carried out by extruding the cheese out of a metering device,such as piston filler (not shown) into the tray 12. When a desiredamount of cheese product has been metered out, the cheese product willsettle into the tray 12. The open tray 12 is then closed and sealed withthe lid 14 by pushing the lid 14 into the tray 12, or by lockinglyengaging the projections 39 into the grooves 29, or by pressing bothflanges 28 and 38 together to heat seal the sealant layers 41 depositedon the corresponding surfaces of the tray flange 28 and the lid flange28.

Preferably, one may apply a printed label (not shown) or wrap thecontainer with a printed paperboard sleeve (not shown) to providepackaging information on the container 10.

While a preferred embodiment of the invention has been described, itshould be understood that the invention is not so limited, andmodifications may be made without departing from the invention. Forexample, the raised marks may be formed into a bottom surface of therecesses panel so that they are potentially visible to the consumer, andcorresponding marks are transposed on a topside surface of the cheeseproduct when the lid is initially locked together with the tray 12.These transposed surface markings, represented by numbers or letters, orboth, provide the consumer with an easy indication of the productincrements and their corresponding sizes. The marks may include inks,dyes, food colorings, and the like. Therefore, it is intended that allsuch variations and modofications fal within the scope of the appendedclaims, and equivalents thereof.

1. A thermoformed container comprising: a tray having walls that join abottom surface and form an opening opposite the bottom surface, whereinthe walls are curved where they join the bottom surface; a tray flangesurrounding the opening and extending outwardly from the walls; a lidhaving a recessed panel surrounded by a peripheral sidewall, wherein thelid and the tray are configured to lock together; a lid flangesurrounding the peripheral sidewall and extending outwardly therefrom;and marks on the bottom surface that are configured to indicate measureincrements.
 2. The thermoformed container of claim 1, wherein the marksfurther comprise numbers.
 3. The thermoformed container of claim 1,wherein the marks further comprise letters.
 4. The thermoformedcontainer of claim 1, wherein the marks are configured to indicatesubstantially equal increments.
 5. The thermoformed container of claim1, wherein the marks are transposed on a contained product, therebyenabling easy division of the contained product into correspondingincrements when the contained product is removed from the thermoformedcontainer.
 6. The thermoformed container of claim 1, wherein therecessed panel comprises a structure that enables the lid to be pusheddown into the opening to lock the lid and the tray together.
 7. Thethermoformed container of claim 1, wherein a bottom surface of the lidflange substantially mirrors structurally at least a portion of an uppersurface of the tray flange for sealing purposes.
 8. The thermoformedcontainer of claim 1, wherein the tray flange and the lid flangecomprise structures that form a hermetic seal.
 9. The thermoformedcontainer of claim 8, wherein the flange of the tray and the flange ofthe lid further comprise sealant layers to hermetically seal thecontainer.
 10. The thermoformed container of claim 8, wherein thehermetical seal comprises a peelable seal that enables the lid to beeasily removed from the tray.
 11. The thermoformed container of claim 1,wherein the tray and the lid comprise substantially rigid plastic filmstructures.
 12. The thermoformed container of claim 1, wherein the trayand the lid comprise substantially semi-rigid plastic film structures13. The thermoformed container of claim 11, wherein the substantiallyrigid plastic film structure comprises an oxygen barrier material. 14.The thermoformed container of claim 12, wherein the substantiallysemi-rigid plastic film structure comprises an oxygen barrier material.15. The thermoformed container of claim 11, wherein the substantiallyrigid plastic film structure comprises a release agent.
 16. Thethermoformed container of claim 12, wherein the substantially semi-rigidplastic film structure comprises a release agent.
 17. The thermoformedcontainer of claim 13, wherein the release agent comprises glycerol monostearate.
 18. The thermoformed container of claim 14, wherein therelease agent comprises glycerol mono stearate
 19. The thermoformedcontainer of claim 1, wherein the tray walls further comprise groovesthereon and the lid sides further comprise projections thereon.
 20. Thethermoformed container of claim 19, wherein the projections engage thegrooves when the lid and the tray are brought together.
 21. Thethermoformed container of claim 19, wherein the projections comprisestructures arranged in series.
 22. The thermoformed container of claim19, wherein the lid and the tray are configured such that a downwardsliding movement of the lid into the tray is arrested when the lidprojections engage the corresponding grooves of the tray.
 23. Thethermoformed container of claim 1, wherein the tray and the lid furthercomprise corresponding locking lugs.
 24. A thermoformed container forholding a food product comprising: a tray having walls that join abottom surface and form an opening opposite the bottom surface, whereinthe walls form a curved surface where they join the bottom surface; atray flange surrounding the opening and extending outwardly from thewalls; a lid having a recessed panel surrounded by a peripheralsidewall, wherein the lid and the tray are configured to lock together;a lid flange surrounding the peripheral sidewall and extending outwardlytherefrom; and marks on the bottom surface that are configured toindicate increments of the bottom surface, wherein images correspondingto the marks are transposed on the food product after settling into thetray, thereby enabling easy division of the food product into incrementscorresponding to the marks when the food product is removed from thethermoformed container.
 25. The thermoformed container of claim 24,wherein the marks further comprise at least one of numbers and lettersto indicate a size of the increments.
 26. In combination, a food productin a thermoformed container, the combination comprising: a volume offood extruded out of a metering device and settled into a tray of thethermoformed container; and at least one image on a bottom surface ofthe food product, the at least one image corresponding to at least onemark on a bottom surface of the tray, wherein the at least one imageenables easy division of the food product into increments when the foodproduct is removed from the thermoformed container.